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Einstein Said Nothing Can Move Faster Than Light?

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ty_buchanan | 09:41 Mon 24th Mar 2014 | Science
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Einstein's theory states nothing can move faster than light. How did we get all the way out here with images from the beginning of time still arriving? It is also accepted that the big bang pushed everything out instantaneously. Surely, the big bang theory proves Einstein wrong.
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So are we done now with cosmic inflation violating Einsteins Law and questions over the CMBR then, Colm? Do you still hold to the same views, or has this discussion changed anything?

Sure, you can play Devils Advocate - it can often be a good way of examining the established theory - but playing Devils Advocate usually implies taking a position that one does not agree with, in order to test the argument. Is that your position here?

To be honest ( it could be lack of brain power or lack of coffee) I am not entirely sure what you mean with your latest proposal wrt red shift and photons. It sort of sounds like you are talking about frequency decay of the photons, which in turn sounds like the idea of "tired light" theory or some variation thereof. Would you like to expand your argument a bit more ?
When it come to playing devil's advocate, the old devil himself was apparently not entirely immune to the practice - http://arxiv.org/abs/1402.0132
When it comes to light as opposed to sound the signal of redshift is in the absorption spectra of the elements in the light source. If the movement of the emitter in the direction of the observer leads to a compression of the light waves or photons then the spectra as above are moved towards the blue end of the light spectrum aka the colours of the rainbow and then some. Red shift is when the opposite applies.

But what seems obvious to me is that light compressed at one end can be stretched at the other and vice versa or a bit of both! Hence how do we really know the contemporary universe we inhabit is expanding or contracting from redshift ? For myself I don't think we can.

Luminosity and metallicity do nothing but confirm we are contemporary and the emitters are primordial. Redshift, on the other hand is more ambiguous for the reasons I suggested above.

I believe that it is all a mystery. Nothing appeals to humankind more than a mystery. People can make huge reputations for themselves and become celebrities on TV by offering an orthodoxy of cosmology supported by their peers.

I prefer to be mystified. I don't find the universe more boring or threatening because I don't understand it. The absolute opposite applies. I love it, whatever it is, however it originated, and whatever it finally becomes.
I'm not sure that explanation of red shift is entirely correct. If I understand it the claim would be that all of the shifting of the light spectrum occurred instantaneously during its creation and emission. I'm fairly confident that this is not what the cosmic redshift effect says. Rather, the shifting occurs across the entire path that the light takes, from its source to its ultimate detection. The red shifting is an effect caused by the changing shape and scale of spacetime, and light travels through this change, and continuously shifts more and more as the Universe expands.

I'd have to do a fair amount of reading to be sure of this but I imagine that the effect would not be the same in a contracting Universe at all, but would be reversed. Thus light would blue shift in a contracting Universe. Therefore the observation of a Universal Red Shift across the History of the Universe is, after all, experimental verification of the idea that the Universe is expanding.

Although my guess is that you were probably already going to I'd be slightly wary of the above explanation since I don't do much cosmology and this time I'm going on memory. Most of the explanation above is, I'm sure, on the right lines, but you would be well-advised to do some reading into the subject. In particular, it's important to understand how the "Friedmann-LeMaitre-Robertson-Walker metric" works, since this is the model that most accurately describes the shape of our Universe and is the one that accounts for, among other things, the red shift. Actually, some reading into the subject would be a good idea even if you did take my answer seriously, since across this thread you seem to me to have demonstrated a variety of misconceptions about Modern Cosmology. No harm in that really, but if you are basing your views of the Universe on a series of misconceptions then you shouldn't be surprised if those views turn out to be wrong.
'The universe is expanding, also it's rate of expansion is accelerating.'

How often have you heard this? Yet if red shift is at it's maximum in the distant past and not the present in which this accelerating expansion is supposedly taking place, when red shift is created at the point of photon emission and not at it's point of detection, how can this possibly be the case?

Yes the path of light can be influenced by gravitational fields along it's path hence we have gravitational lensing. I haven't heard of any effect on light in free flight through spacetime that could influence the absorption spectra observed in red or blue shift, which as described (in my Oxford Uni. Dictionary of Physics) as a manifestation of the Doppler effect.

If by view you mean opinion I have no view. I merely have a few misgivings concerning the claims being made by those that do.

I have a copy of Roger Penrose's tome 'The Road To Reality- A Complete Guide To the Laws Of The Universe.' I'll have a look at that when I get a chance, and see what he says about the origins of red/blue shift.
Einstein had never been in the same room with my wife and a cream cake.
I really hope your maths is up to speed then Colm, if you are planning to read Penroses "Road to Reality"; Lots and lots of math in it, especially the first half of the book.

Far too academic for me, I'm afraid.
Red shift does not take place at the source nor at the destination at which it is perceived. Red shift results from the relative widening motion between source and observer and is proportional to the speed of that motion corresponding to the distance between them in an expanding space, which gives rise (npi) to the rising dough analogy. The fact that we observe increasing red shift with distance established (by independent means) is confirmation that the relative motion is likewise taking place in the intervening space rather than at either end of the journey.
It's possible that the universe isn't expanding, it's just that everything in it is getting smaller and smaller, and therefore moving away from everything else. This would also explain the red shift phenomenon.

I submitted a paper on this once, but got no reply.
Penrose turns out to say about as much as my physics dictionary on the subject of red/blue shift. I always meant to start at the tome's beginning and work my way through (if only I could take a couple of years off to do it), instead I often open it an marvel at the hand drawn diagrams with light cones pointing off in all directions.

It seems the consensus has been trying to brush over if or why the sonic light Doppler effect is different from it's sonic equivalent.

I suspect that such could be investigated in lab experiments. But remember that blue shift exists between our more contemporary neighbours in the universe which might explain how we see them colliding with each other, a fate waiting for our own galaxy. To me it seems that if the rate of distancing between the oldest observables in our light cone (as Penrose would say) is observed to be greater then than it is now, then it would seem obvious that expansion was more then than now, which is the exact opposite of what is claimed by the cosmologists who talk to the journalists who in turn get to inform us lot about what we are meant to believe is the truth.

The message us lot receive is that cosmic expansion explains it all and in fact Einstein's claim that nothing can travel faster than the speed of light is wrong in the case of expanding proto-universes.

For me, far too far, far too soon, and I'm not buying into it, not yet at least!
-- answer removed --
//It's possible that the universe isn't expanding, it's just that everything in it is getting smaller and smaller...//

That's pretty much what my other half was saying just this evening, whereupon I tried explaining to her that size is relative. Long story short . . . no cream cake for me tonight. :o/



"...Einstein's claim that nothing can travel faster than the speed of light is wrong in the case of expanding proto-universes. "

He never claimed that. This is the entire point! It's not that some fundamental law is just being broken for the sake of convenience. The law doesn't apply in this case.

Einstein's claim, that has been verified as true, is that energy and information can be transmitted at no faster than the speed of light. The expansion of the Universe carries no energy and no information, and so is free to travel at any speed you like. Rather like a shadow passing across the moon, or the point of contact between a wave and the shore, these things are just arbitrary points carrying no information and no energy.

In terms of the details of cosmic expansion, and when it was fastest and when it wasn't, the pictures is still not fully determined. It was fasted in the first fleeting fraction of a second, and then seems to have proceeded at a varying rate that isn't yet understood properly -- as, among other things, the rate of expansion of the Universe today implies the existence of "dark energy", which is currently just a way of saying "there is something mising, we don't know what".

But in terms of a Universe expanding faster than light, this absolutely doesn't break any cosmic law at all.

* * * * * * * * *

Ludwig, perhaps they never published your paper because by the time it arrived it was too small to read?
A constant feature of scientific theories is that sooner or later they are proved wrong, right from the dawn of history.

The big bang idea is patently silly. Like , say, the phlogiston theory it is an attempt to explain observed phenomena.

Dark matter is equally silly - our sums have a big hole, so we invent something we can't observe that constitutes the bulk of the universe. Phlogiston, anyone?
//our sums have a big hole, so we invent something we can't observe that constitutes the bulk of the universe. //

Sounds awfully like .... God.
Spot on! Early scientists saw the sun cross the heavens, so postulated a chariot driven by a god. Science and religion in agreement...
Established theories are more often refined and seen to be describing certain circumstances, than they are completely overturned and replaced. Of course first attempts to explain things are more vulnerable to being dismissed later as more is known/understood. But I'm unsure why any of your mentioned theories should be described as "silly".
Well that's a narrow and blinkered view of Science History. Rather a lot of theories end up being proved right. Such as, in no particular order: Kepler's Laws and model of the Solar System; Newton's Theories of Gravity, Light and motion; Hooke's cell model of life and his law of elasticity; The Navier-Stokes model of fluid dynamics; Fraunhofer's model of diffraction; Fresnel's model of diffraction; The Maxwell-Heaviside equations of Electrodynamics; Thermodynamics as formulated by the late 19th-Century scientists such as Maxwell, Kelvin, Boltzmann, Gibbs etc.,... all these theories and many more I've not been able to think of have survived the test of time and experiment and are certainly not silly or discarded, nor is there any reason to think that will change.

The theories which do get discarded are the ones with no evidence. The Big Bang Theory has plenty of evidence, and as such is now in a place where what will change is the fine detail, not the idea as a whole. No-one ever had any evidence for phlogiston.
Narrow and blinkered, perhaps, and not completely serious.
It's just that there's all this clever hair splitting going on here when we don't understand the basics it's all based on.

The big bang and dark matter are not supported by any scientific observations - they merely form a basis to explain observed phenomena.

Try this - a very clever scientific beetle has got into a bottle lying on its side. It observes that it can crawl the length of the bottle, but that it slips back if it tries to crawl up the side.

It observes that there is a force acting upon it, which it can't understand. It might postulate some mysterious force.

If it were a religious beetle, it would say that a divine influence intended it to travel only in one direction.

The point is that the beetle is incapable of understanding the nature of the bottle.

Scientists are stuck in a bigger and better bottle which they can't understand. Newton, Einstein and the rest merely set out the science behind moving inside the bottle.
and no, I'm not a Nietzschean...

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